This is a connector for a 5 pole kite (3/8" poles of varying lengths). It is based on a kite design from my youth (70's Green Giant Kite)
The edges on the front flat side should be smoothed out so they don't tear the kite when flying. I haven't quite figured out how to do that with the 2 planes in Sketchup. Also the pole supports might be a little thin @ .120". I thought I had it closer to 1/8 (3/16" might be where it should be). Dimensions are in inches.